Which of the following controls is MOST important for ensuring the integrity of system interfaces?

 File checksums are values that are calculated from the contents of a file and can detect any changes or corruption in the file. They are used to verify that the files that are transferred or processed through system interfaces are not altered in any way. File checksums are more effective than periodic audits, file counts, or IT operator monitoring, which are other types of controls that can help ensure the integrity of system interfaces, but they are not as reliable or timely as file checksums.